Air conditioning



s, c 131.00m

Nov. 10, 1931.

AIR CONDITIONING Filed Aug. ll, 1950 (gm/uente@ VO 0v H l/ attenua@ Patented Nov. 10, 1931l UNITED STATES PATENT OFFICE SAMUEL C.`BLOOM, 0F CHICAGO, ILLINOIS, ASSIGNOR T0 THE NEW YORK AIR BRAKE COMPANY, .t CORPORATION F' NEW JERSEY AIR CONDITION ING AppIication led August 11, 1930. Serial No. 474,534.

interchanger, the thermostatically controlled valve functioning to prevent untreated air from attaining freezing temperatures in its passage through the regenerative heat interchanger.

The invention is applicable generally to refrigerative conditioners of the type specified, lbut is designed particularly for use on units developed for conditioning compressed air for industrial uses, for example, the compressed air used in railway air-brake systems. It will be described in connection with a cooling system known to me, but invented prior to the present invention,` in which the deposition o frost in low temperature conditioners vis minimized by the use of substantially non-turbulent How of air through the conditioner.

In the operation of such a device, droplets of moisture form in the air stream passing the refrigerated surface, and grow to a size favorable to mechanical separation of the droplets from the air at a point beyond the favorable to mechanical separation of the character is somewhat sensitive to changes of temperature in -the deviceyand the present invention by stabilizing conditions at the entrance to the conditioner roper, assists in steadying the operation o the conditioner.

A preferred embodiment of the inventionis illustrated in the accompanying drawings, in which,--

Fig. 1 is a view, partly in vertical section,

and diagrammatic in character, showing an installation embodying the invention.

Fi 2 'is a vertical axial section through the t ermostatic valve.

'are' connected together by an inlet manifold Fig. 3 is a vertical axial section through one type of moisture separator.

The conditioner proper comprises two` refrigerative shells, the iir'st stage shell being indicated at 6 and the second stage shell at 7. The intake to the first stage shell is-shown at 8 and the discharge at 9. Theconnection ll leads from the connection 9 to the intake connection 12 of the second stage. The second stage has a tapered or Haring head i3 designed to produce a gradual change of cross section and thus reduce turbulence There is also a flaring discharge head 14 having a discharge connection 15 leadin to a moisture separator 16. The preferred type of moisture separator is shown on an enlarged scale in vertical axial section in Fig 3..

1n such separator, the air is delivered to a central chamber surrounded by a plurality of blades or vanes 17 arranged in a circle in secant relation, so that air entering the separator through the connection l5 is given a whirling motion which throws moisture droplets against the interior of the shell of the separator 16. Moisture thus precipitated W is drained off at the connection 18 and is prevented from flowing to the air-dlscharge connection 19 by an annular dam or bame 21. A plate-like lbame 22 connects the lower ends of the blades y17 and further protects the outlet connection.

Mounted in the shell 6 are a pluralit of vertically arranged plate-like hollow cel s or leaves, one of which appears at 23. These B5 24 through which a volatile liquid refrigerant is delivered to the interior of the leaves. The leaves are further connected by a suction. manifold 25 through which evaporated refrigerant is drawn from the leaves. A plurality of staggered baiiles 26 increase the velocity and turbulence of `flow through the shell 6. In the operation of the device, the leaves 23 are maintained at a temperature near, but slightly above, the freezing point of water, so that frost does not tend to form in the shell 6. Hence, turbulent How is practicable and increases the heat transfer. recipitated moisture is drained. away through aconnection 27 Air, partially freed from moisture by passage through the shell 6, Hows through the pipe 11 to the shell 7, through which the flow is as nearly non-turbulent as it is practicable to attain. Non-turbulence is approached by adopt-ing approximately stream line forms for passages and by reduction of the air-flow velocity to the practicable minimum.

ln passing through the shell 7 the air ows past a plurality of vertical leaves or cells 28 similar to the `leaves 23. These yare connected by al supply manifold 29 and a suction manifold 31, similar to the parts 24 and 25 above described. There are no bames and the iiow is relatively slow. Little moisture is precipitated in the shell 7, and such as does precipitate is drained off by the drain 32. It and the drain 27 have a common discharge through a valve 33, of any suitable form.

in flowing past the refrigerated leaves 28, which are maintained at a temperature substantially below the freezing point of water, the effect is to stimulate the formation and growth of waer droplets in the air current. The parts are so designed that by the time the air reaches the separator 16, the droplets will have attained a size favorable to mechanical separation. nly such droplets as actually contact the leaves will form frost.

ln order to recover part of the refrigerative effect represented by the low temperature of the outgoing air, it is desirable to use a regenerative heat-interchanger. This is indicated as of the shell and tube type. The air discharging from the connection 19 of the separator 16, ows through a pipe 34 to the left hand end of an interchanger shell 35. This shell contains a number of tubes 36, whose ends are fixed in tube sheets 37. The tube sheets 37 are spaced from the heads 38 of the shell 35 to form manifolds 39. Air coming from the compressor, enters through the pipe 41, flows by way of the left hand manifold 39 to the interior of the tubes 36,

passes thence through the tubes 36 to the right hand manifold 39, and thence by the pipe 42 to the inlet connection 8 of the shell 6. Treated air entering the shell by way of pipe 34 liows around the tubes 35 in a spiral path defined by the spiral baiile 43, a'nd nally discharges from the shell by Way of connection 44 which leads to the main reservoir or other point of storage or use not shown).

lt will be observed that the treated air and the untreated air which pass in heat exchanging relation within the shell 35, flow in the same general direction. Counterlow might be secured, if desired, bya simple reversal of connections.

All three shells 6, 7 and 35, and their intermediate pipe connections are encased in a mass of insulation 45, to prevent the inleakage of heat.

The conditioner just described, is illlustrated as typical of various devices which maybe used. it is not of my invention. However, because of the operative characteristics of the conditioner, the regulative control here described and claimed, develops peculiar utility in connection with condition- ,ers of this general type.

The refrigerative circuit includes a suction line 48, controlled by a stop valve 49 and an automatic pressure regulating valve 50 of any suitable type. This leads from the manifold 25. There is a second suction line 51, controlled by a stop valve 52, and leading from the manifold 31. These two lines deliver to the suction connection 53 of the refrigerant compressor 54. The pressure regulating valve 50 operates to preserve in the evaporator leaves 23 a pressure higher than the suction pressure at connection 53. The purpose is to maintain leaves 23 near to but above freezing temperature, while the leaves 28 are below freezing temperature because subject to a lower vapor pressure.

The compressor 54 is shown as driven through a belt 55 by a motor 56, here understood to be of a substantially constant-speed type. Consequently -the compressor operates at a substantially constant displacement rate. The discharge connection from the compressor 54 leads to a condenser 57, which may be of the air-cooled, or any other type. Refrigerant, liquefied in the condenser 57, drains to a receiver 58, from which it is drawn by a high pressure liquid line 59. lt is delivered through valves 61 and 62, which are indicated as manually adjustable (but may be of any suitable type) to the intake manifolds 24 and 29.

The system illustrated is intended to be typical of any substantially uniformly operating refrigerative system, having some means for regulating and differentiating the refrigerative effect developed in the shells 6 and 7, so that these shells are maintained at the desired different temperatures. There are various ways of accomplishing the result. The arrangement shown is perhaps the simplest.

A portion of an ordinary air-brake compressor is diagrammatically indicated at 63. Tt delivers to the body 64 of a three-way valve.

Referring to Fig. 2, as to the construction of this valve, 65 is the inlet connection, 66 is a discharge connection which leads to anatmospherically cooled coil 67, and 68 is a discharge connection to a by-pass 69. Thelbypass 69 and the discharge end of the coil 67 are connected at 71 to pipe 41 which delivers air to the regenerative interchanger. The valve head 72 is mounted on a longitudinally reciprocable stem 73, and shifts between two opposed seats 74 and 75. Tn its uppermost position, it directs all the air through the bypass 69, and in its lowermost position it diincassa i'ects` all the air through the coil 67. ln interin varying proportions.

The stem 73 is actuated by a metallic bellows or motor 76 which is iixed at its upper end to the upper end of stem 73., and is sealed at its lower end to the globe or chamber 77 which surrounds the bellows 7 6. v 'llhe globe 77 is connected by a small liquid filled pipe 78 with a bulb 79 which contains a trapped volatile liquid and which ispreferably mounted in the pipe 42- between the regenerative heat exchanger' shell 35' andthe intake 8, which leads to the iirst refrigerative stage of the conditioner. A spring 8l opposes the action of the motor. lllhe particular thermostat illustrated was chosen because it is a simple and familiar type. Any preferred type may be substituted.

lf the temperature of the bulb 79 rises, an increased pressure will be generated in the pipe 7 8; and the ralve stem 7 3 will be moved downward; directing an increased proportion ot air through the cooler 67. A tall ot' temperature exerts the opposite eifect. ln this way there is edected a thermostatic control which tends to maintain substantially constant the' temperature of air leaving the regenerative heat interchanger.

The thermostatic control is such as to preclude attainment by` air iiowing from shell lo-shell 6, of freezing temperatures, and ordinarily the regulated temperature will be. considerably above freezing. 'lhepetiect is to give a range of control commensurate with seasonal temperature changes of the atmosphere. p

The cooling eiiect of coil 67 issubject to seasonal variation; while the cooling effect attained in the regenerative heat-interchanger shell 35 is more nearly uniform. rlhe relation of the two eii'ects must be such that Within the normal range oi atmospheric temperature; the thermostat 79 can exert the desired control. 'ilhis involves caretul proportioning of heat transfer surfaces.

TWhile i prefer an atmospherically cooled coil 67, such as is shown; any type oi1 cooler which does not impose a load on the refrigeratire compressor 5ft; might besubstituted.

What. is claimed isfil. rlhe combination, of a compressor; a re- Arigerative conditioner for condensing vapors from gas compressed by said compressor; a refrigerating machine connected said reirigerative conditioner to furnish the refrigeration required tliereby; an atmospheric cooler: valve means for delivering gas from said compressor to said conditioner, either directly or through said cooler in varying proportions: and a thermostat subject to the teinniediate positions, it directs air through both perature in a portion of said conditioner and connected to actuate said valve means.'

2. The combination of a'compressor; a refrigerative conditioner Jfor condensing vapors from gas compressed by said compressor; a refrigerating machine connected to said refrigerative conditioner to furnish the refrigeration required thereby; a cooler operated independently of said refrigeratin-g inachine; valve means for delivering-*gas from said compressor to said conditioner, either directly or through said cooler in varying proportions; and a thermostat subject to the temperature in a portion of said conditioner and connected to actuate said valve means.

3. The combination of a compressor; a refrigerative conditioner for condensing vapors from gas compressed by said compressor; a heat exchanger connected to eifect a heat interchange between treated and untreated gas flowing from and to said conditioner; a refrigerating machine connected to said refrigerative conditioner to turnishj the refrigeration required thereby; an atmosphericcooler; valve means for directing gas from said compressor't'o said conditioner in varying proportions directly and through said cooler; and a thermostat subject to the temperature of the gas entering saidconditioner from the heat exchanger and connected to actuate said valve means.

4. rThe combination of a compressor; a refrigerative conditioner `ior condensing vapors from gas compressed by said compressoir; a heat exchanger connected t0 efi'ect a heat interchange between treated and untreated gas iiowing 'from and to said-conditioner; a retrigerating machine connected to said reiirigerative conditioner to furnish the refrigeration required thereby; a cooler operated independently. of said refrigerating machine; valve'means or directing gas from said compressor to said conditionerl in' varying proportions directly and through said cooler; and a thermostat subject to the temperature of the'gas entering said conditioner :from the heateiichanger and connected to actuate said valve means.

5. The combination of a compressor; a refrigerative conditioner for condensing vapors from gas compressed by said compressor; a `heat exchanger connected to edect a heat interchange between treated and untreated gas owing from and to said conditioner; a rerigerating machine connected to said .refrigerative conditioner to furnish the refrigeration required thereby; an atmospheric cooler; valve means tor delivering gas from said compressor to said conditioner; either directly orthrough said cooler in varying proportions; an abutment and an opposing spring connected to operate said valve in reverse directions; and a bulb containing a volatile liquid connected to transmit vapor pressure developed by said liquid to said abutment, said bulb being subject to the temperature oi gas flowing from the exchanger to the refrigerative conditioner.

(i, The combination of a compressor; a reiop :Erigerative conditioner for condensing vapors from gas compressed by said compressor; a heat exchanger connected to eect a heat interchange between treated and untreated gas iowing roniand to said conditioner; n .rerigerating machine connected to seid refrigerative conditioner to furnish the refrigeration required thereby; a cooler operated independently of said refrigerating machine; valve means for delivering gas from said compressor to said conditioner, either direct- 1y or through said cooler in varying proportions; an abutment and an 'opposing spring connected to operatesaid Valve in reverse directions; and a bulb containing a volatile liquid connected to transmit the vapor pressure deveiopedby said iiquidto said abutment, said bulb being subject to the temperature of gas flowing from the exchanger to the rerigerative conditioner.

7 The combination of a compressor; a rerigerative conditioner of the type inciuding refrigerated surfaces; means `for conducting gas compressed by the compressor pest at least the colder part of said rerigereted surfaces with substantially non-turbulent i'ioW; a moisture separator in the path of the gas beyond said refrigerated surfaces a heat exchanger connected to eiect a heat interchange between 'treated end .untreated gas dor/ving :troni and to said conditioner; a re'riverating machine connected to refrigerate said refrigerated surfaces; a cooier independent of said re'frigerating piant; valve ineens for delivering gas rorn said compressor `to seid conditioner either directly or through said cocier,l in Varying proportions; and e thermostat subject to the temperature of the gas entering the reilrigeratiye conditioner from the eX- changer and connected to sctnate seid naive l iin testimony whereof havesigned' my neme to this speciiicstion.

SAE/HEEL C. 

